Judgment :- Paripoornan, J. The Revenue is the Petitioner in both the revisions. The same assessee is the respondent in both the cases. The matter relates to the assessment year 1987-88. The respondent is an assessee under the Kerala General Sales Tax Act. It is a dealer in Jewellery. The sales Tax Appellate Tribunal disposed of T.A.No.799/89, filed by the assessee, and T.A. 201/90, filed by the Revenue, against the same order passed by the first Appellate authority-additional Deputy Commissioner (Appeals), dated 17-11-1989, by a common order dated 22-2-1991. For the assessment year 1987-88, the assessee reported a taxable turnover of Rs.14, 46,783.43. The books of accounts and the returns were rejected by the assessing authority and he determined the taxable turnover at Rs.93, 74,230/- . In determining the taxable turnover aforesaid, the assessing authority adopted the basis, of three times the running stock value. In first appeal, the Deputy Commissioner of Sales tax, Ernakulam reduced the addition to two times the running stock. Against the relief granted to the assessee, the Revenue filed T.A.No.201 of 1990 before the Sales tax Appellate Tribunal. Not satisfied with the relief granted by the first appellate authority, the assessee filed T.A.No.799 of 1989 before the Appellate Tribunal. Both the appeals were heard together and disposed of by a common order dated 22-2-1991. After adverling to the facts and circumstances in detail, the Appellate Tribunal allowed the appeal filed by the assessee in part and held that 100% addition to the reported taxable turnover will meet the ends of justice. The appeal filed by the Revenue was dismissed. That is why the Revenue has filed two revisions against the common order passed by the Appellate Tribunal dated 22-2-1991. 2. We heard counsel for the Revenue - senior Government Pleader Mr. James. The Sales tax Appellate Tribunal upheld the rejection of accounts. On an inspection conducted at the business place of the assessee, considerable stock variation was found out and the assessee itself compounded the offence of non maintenance of correct and complete accounts, by paying a compounding fee of Rs.3,700/-. The gross profit was abnormally high. The closing stock was undervalued. The wastage accounted was seen excessive. There was stock variation. The difference in quantity was found in respect of old gold purchases. The explanation offered by the assessee for the various defects were considered and some of the explanations were accepted. The gross profit was abnormally high. The closing stock was undervalued. The wastage accounted was seen excessive. There was stock variation. The difference in quantity was found in respect of old gold purchases. The explanation offered by the assessee for the various defects were considered and some of the explanations were accepted. Even so, it Vas evident that there was stock variation of a substantial nature and for the offence of non maintenance of true and correct accounts, the assessee itself came forward with a compounding application. The offence was compounded by paying a fee of Rs. 3,700/-. Even before the Appellate Tribunal the assesses did not plead for acceptance of accounts. On facts, it is common ground that the rejection of accounts was justified. 3. The only serious question that arose for consideration before the Sales tax Appellate Tribunal and still canvassed before us is regarding the reasonableness of the estimate made. On this aspect, we should at once say that reasonableness of the estimate to be made in a best judgment assessment, is largely an exercise to be done on a case to case basis and ordinarily a decision made by the final fact finding authority is not open to review in the revisional court, unless the finding is vitiated in law. If a finding of fact is entered by the Appellate Tribunal, by ignoring relevant facts, or by adverting to irrelevant facts or factors, or by assuming facts or circumstances which have no existence or if the finding is arrived at by posing a wrong question or failing to pose the proper question or in any manner the finding is unfair, perverse or arbitrary or irrational, this Court can interfere with the said finding in exercise of the revisional powers under S.41 of the K.G.S.T.Act. 4. In this case, the assessing authority estimated the taxable turnover at three times the running stock. In first appeal, it was reduced to two times. The Appellate Tribunal adopted a different basis and held that the taxable luin over of the assess need only be estimated by making 100% addition to the reported taxable turnover (ad hoc addition). As a final fact finding authority, it was open to the Sales Tax Appellate Tribunal to re-evaluate and re-appreciate the entire facts and circumstances. The Appellate Tribunal adopted a different basis and held that the taxable luin over of the assess need only be estimated by making 100% addition to the reported taxable turnover (ad hoc addition). As a final fact finding authority, it was open to the Sales Tax Appellate Tribunal to re-evaluate and re-appreciate the entire facts and circumstances. If more than one method or approach is possible, any alternative method can be resorted to estimate the quantum in a best judgment assessment. The quantum to be made in a best judgment assessment should be rational and fair in all circumstances of the case and it can be based on a reference to comparable cases, or by reference to the turnover of the assessee himself in the previous years or by reference to running stock or by making an ad hoc addition on percentage basis, which by and large should have nexus or be germane to relevant facts (The said methods are not exhaustive). On facts, the Revenue should be able to substantiate that out of the alternatives, a fair approach/method has been adopted. In this case, the Tribunal took the view that the estimate of addition should not be made with reference to running stock. It should be remembered that for estimating the turnover adopting the multiple of running stock is not the only or exclusive basis or approach. In this case, the running stock for the year amounts to Rs.31, 24,742/-. The assessee pleaded that he was forced to keep such a high stock of gold jewellery due to special circumstances, such as his business place is located in a very prominent area in Ernakulam Town, viz. M.G. Road, where there are so many other leading jewellery shops, including Bhima Jewellery, etc. and so in order to attract customers, it had to keep a high stock, both in weight and in varieties. The Tribunal adverted to the stock variation found out during the inspection, which is only 1 %of the total stock held during the year and held that it is negligible. The Appellate Tribunal also adverted to the fact that the addition made by the assessing authority is about 500% above the value of alleged irregularities. The Tribunal adverted to the stock variation found out during the inspection, which is only 1 %of the total stock held during the year and held that it is negligible. The Appellate Tribunal also adverted to the fact that the addition made by the assessing authority is about 500% above the value of alleged irregularities. After advertence to the relevant facts and circumstances, the Appellate Tribunal concluded in Paragraph 9 of its order thus: "On an analysis of the various aspects like the previous years' assessments, the gravity of the stock difference found at the inspection, the quantum of stock available at the time of Inspection, the locality of the business of the assesses, the competitive in he has to face at this locality, the existence of very prominent jewellers like Dhima Jewellery, etc. very near to the assessee's business, etc. we hold that the estimate on the basis of running stock cannot be adopted in this case for estimating the turnover for the year. Considering the quantum of stock difference noticed at the inspection and other circumstances, we hold that an estimate of taxable turnover making 100% addition to the reported taxable turnover ofRs.14, 46,783.43, will be more reasonable and will meet the ends of justice in this case. We therefore, direct the assessing authority to modify the assessment and fix the taxable turnover of the assessee for the year in question adding 100% towards probable omissions and suppressions to the taxable turnover returned. To this extent, we modify the assessment and in all other respects, the assessment will stand". 5. The facts found by the Appellate Tribunal or proved before it, amply demonstrate that the method of estimating the turnover by reference to running stock will be unreasonable and unfair. The Appellate Tribunal has applicdits mind and has not acted mechanically. The various aspects highlighted by the Appellate Tribunal in paragraphs 8 and 9 of its order dated 22-2-1991 justified another tenable alternative. Method to be adopted by the Appellate Tribunal in fixing the quantum of estimate, in a best judgment assessment. Demonstrate and valid reasons have been given therefore. The Appellate Tribunal found that the estimate on the basis of running stock cannot be adopted in this case which will be irrational or unfair and the ends of justice will be met by making 100% addition to the reported taxable turnover towards probable omissions and suppressions. Demonstrate and valid reasons have been given therefore. The Appellate Tribunal found that the estimate on the basis of running stock cannot be adopted in this case which will be irrational or unfair and the ends of justice will be met by making 100% addition to the reported taxable turnover towards probable omissions and suppressions. The finding of the Appellate Tribunal is largely a question of fact. It cannot be said to be unfair or irrational. Honest guesswork is permissible in making best judgment assessment. It is true that in fixing the estimate in a best judgment assessment, one of the bases adopted is the multiple of running stock. We again stress the fact that it is not the sole basis. If circumstances in a particular case do not warrant the adoption of that basis, but any other alternative basis, it is opcnlo the fact finding authority to make a best judgment assessment on any other tenable or valid alternative basis. We hold so. 6. The order of the Appellate Tribunal does not suffer from any error of law. In choosing one of the alternatives, the Appellate Tribunal - the final fact finding authority - cannot be said to have committed any error of law in fixing the estimated turnover in best judgment assessment. We are of the view that the common order passed by the Appellate Tribunal dated 22-2-1991 does not merit interference in revision. The Tax revision cases are without merit. They are dismissed.